Pericyte-derived heme-binding protein 1 promotes angiogenesis and improves erectile function in diabetic mice

PURPOSE: To comprehensively evaluate the effect on angiogenesis of heme-binding protein 1 (Hebp1) in the treatment of diabetes-induced erectile dysfunction. MATERIALS AND METHODS: Mouse corpus cavernosum endothelial cells and pericytes were used for in vitro study. Four groups of mice were used: control nondiabetic mice and streptozotocin-induced diabetic mice receiving two intracavernous injections of phosphate-buffered saline, Hebp1 (1 µg), or Hebp1 (5 µg). The function of Hebp1 in diabetic conditions was evaluated by tube formation assay, aorta ring assay, migration assay, intracavernous pressure, immunofluorescence staining, and Western blot experiments. RESULTS: We report that Hebp1 is more highly expressed in mouse corpus cavernosum pericytes and can effectively promote endothelial cell angiogenesis under high-glucose conditions. Following exogenous administration of Hebp1 protein, we found that elevated Hebp1 levels can improve the erectile function of diabetic mice, which is achieved by reducing reactive oxygen species levels and activating the PI3K/AKT/eNOS signaling pathway. CONCLUSIONS: Our findings demonstrate that Hebp1 can promote angiogenesis and improve erectile function under diabetic conditions.